Governors, members of Congress and those aspiring to elected office are facing the uncomfortable question of whether to support the coarse billionaire, who has driven the debate into a smash-mouth campaign on delicate issues like race, or distance themselves from a celebrity many worry is hijacking their party.

It is fast becoming the defining question of the 2016 election: When it comes to Trump, which side are you on?

"It could very well be a turning point, for the entire political system as much as for the Republican Party," said Julian E. Zelizer, a Princeton University history professor who has written extensively about American politics.

"As the Republican electorate makes its position known, which they have, Republican leaders need to do the same," he said. "Given just how controversial he is, all of them realize their decision could have long-term ramifications on their careers and legacy."

"I don't even want to get into that. ... God," said John H. Sununu,...

Editor's note: Back in February, Times political writers assessed how Donald Trump might govern if he was elected President. Here’s what they had to say:

President Trump.

A lot of people have trouble putting those two words together.

"I don't even want to get into that. ... God," said John H. Sununu,...

(David Lauter, Michael Finnegan and Noah Bierman)

It's perhaps no surprise, then, that a simple yes-or-no answer does not come easily to many Republican leaders. The response often entails complex personal and political calculations that show just how much Trump's unorthodox ascent is roiling the party he only recently adopted as his own.

They can try to fight Trump's groundswell of popular support — as a new super PAC backed by a wealthy family and staffed by a top former Jeb Bush aide hopes to do. Or they can embrace a new era of Republicanism in the age of Trump. On one side they face potential retaliation from GOP establishment leaders who oppose Trump; on the other they risk the wrath of voters who support the billionaire.

It could very well be a turning point, for the entire political system as much as for the Republican Party.— Julian E. Zelizer, a Princeton University history professor who has written extensively about American politics

House Speaker Paul D. Ryan offered a textbook display this week at the discomfort many leaders are facing. He felt compelled to distance his party from Trump's failure over the weekend to immediately disavow David Duke, former grand wizard of the Ku Klux Klan.

"I want to be very clear about something: If a person wants to be the nominee of the Republican Party, there can be no evasion and no games," Ryan told reporters at the Capitol. "They must reject any group or cause that is built on bigotry."

But he could not bring himself to come out against Trump. "My plan is to support the nominee," Ryan said.

Of course, Trump's presidential rivals have no such hesitations. On the campaign trail, rival Sen. Ted Cruz of Texas argued that Trump's hybrid political positions leave strict conservatives nowhere to go but to his own campaign, and Sen. Marco Rubio of Florida has capitalized on the historical significance of the moment.

"What you are hearing now is how do we prevent the party of Reagan and Lincoln from being taken over by someone who for days refused to condemn the Ku Klux Klan and someone who quite frankly is carrying the most elaborate con job we have ever seen in politics," Rubio said Wednesday. "We are going to do whatever it takes to ensure that I am not only the nominee, but the Republican Party does not fall in the hands of someone like Donald Trump."

Trump's backers appear bemused at the hand-wringing as their candidate sidelines the party establishment with more voter enthusiasm than any GOP nominee has generated in years.

"The establishment Republicans are all bed-wetting over this and they don't seem to understand that we have an election," former Arkansas Gov. Mike Huckabee said Wednesday. "At some point we need to recognize that if you want to oppose Donald Trump, do it, but don't pretend that somehow that all these voters who have gone out and voted for him are stupid. They're not stupid. I'll tell you what they are: They're angry and they're angry at the very establishment who is going nuts because Donald Trump is doing so well and they don't get it that they're the problem."

For some Republican leaders, the decision to dump or jump has been easy.

Jeff Sessions, the four-term senator from Alabama who has fought Rubio on immigration, eagerly slipped on a Trump "Make America great again" hat during a weekend endorsement rally.

Anti-immigration leaders in Arizona — former Gov. Jan Brewer and Sheriff Joe Arpaio — fall into this group, as does Kris Kobach, the Kansas official who has also fought immigration.

New Jersey Gov. Chris Christie surprised many by endorsing Trump last week, and has seen a strong backlash. He appeared somewhat uncomfortable Tuesday night as he stood behind Trump while the candidate made a televised speech.

On the other side, Republicans lining up against Trump include Meg Whitman, the business executive who ran for California governor, and a growing list of members of Congress, including Nebraska Sen. Ben Sasse, who posted a lengthy explanation on his Facebook page.

"If Donald Trump becomes the Republican nominee, my expectation is that I will look for some third candidate — a conservative option," the first-term senator wrote. "I suspect I am far from alone."

And there are those testing the waters. "Trump's shift toward inclusiveness, team effort and unity was vitally important," former GOP presidential hopeful Newt Gingrich said in a tweet Tuesday. "He has to build a Reagan-like inclusiveness to win this fall."

The difficulty for many who want to stop Trump is that at this stage of the nominating process, they have no plausible solution to counter his vast popularity.

"If the field doesn't consolidate, Trump's going to win," said Sen. Lindsey Graham (R-S.C.), who had backed former Florida Gov. Jeb Bush until Bush dropped out of the race. "At the end of the day Donald Trump is not a conservative. If he becomes the face of the party, then I think we're going to have a hard time winning elections in the 21st century."

Even the normally loquacious Sen. John McCain refused to take a side in the battle over Trump's imprint on the party. "I'm running for reelection," McCain said. "That's where I'm coming down."

Sen. John Cornyn of Texas said he was flattered by the notion "that people really care what senators think," but then the Senate's No. 2 Republican declined to say what he thought.

Democrats were eager to share their views. Senate Minority Leader Harry Reid of Nevada called Trump the GOP's "Frankenstein" — a candidate engineered from years of Republican rhetoric.

"I think they're trapped," Reid said Wednesday in a brief interview. "I think it hurts their party for a generation or two to come."

A version of this article appeared in print on March 03, 2016, in the News section of the Los Angeles Times with the headline "Trump's success has GOP leaders torn" —
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